Plasma Waves near the Electron Cyclotron Frequency in the Near-Sun Solar Wind
Plasma Waves near the Electron Cyclotron Frequency in the Near-Sun Solar Wind
复制标题
近太阳太阳风中电子回旋频率附近的等离子体波
DOI：
10.3847/1538-4365/ab4c3b
复制
发表时间：
2019
期刊：
影响因子：
--
通讯作者：
M. Stevens
中科院分区：
文献类型：
--
作者：
D. Malaspina;J. Halekas;L. Berčič;D. Larson;P. Whittlesey;S. Bale;J. Bonnell;T. Dudok de Wit;R. Ergun;G. Howes;K. Goetz;K. Goodrich;P. Harvey;R. Macdowall;M. Pulupa;A. Case;J. Kasper;K. Korreck;R. Livi;M. Stevens
帕克太阳探测器前两次绕太阳运行的数据显示，太阳风向太阳的50个太阳半径充满了等离子体波和不稳定性。在电子回旋频率（fce）附近，等离子体波功率的增强最为显著。这种波能大部分集中在0.7 fce和fce附近的电场波动中，两个频率的强谐波都延伸到fce以上。至少观察到两种不同的，通常是并发的波模式，初步确定为静电哨声模式波和电子伯恩斯坦波。波浪间隔的持续时间从几秒到几小时不等。随着与太阳距离的减小，这些近太阳波的振幅和探测次数都显著增加，这表明它们在近太阳太阳风中电子种群的演化中起着重要作用。发现这些波的探测与太阳风电子居群的性质（包括电子核心漂移）之间存在相关性，这意味着这些波在调节太阳风电子携带的热通量中起作用。这些近面波的观测发现与低水平磁湍流的近径向太阳风磁场结构密切相关。提出了这些波增长的一个设想，这意味着低湍流的近径向磁场区域是太阳附近太阳风结构的一个突出特征。
Data from the first two orbits of the Sun by Parker Solar Probe reveal that the solar wind sunward of 50 solar radii is replete with plasma waves and instabilities. One of the most prominent plasma wave power enhancements in this region appears near the electron cyclotron frequency (fce). Most of this wave power is concentrated in electric field fluctuations near 0.7 fce and fce, with strong harmonics of both frequencies extending above fce. At least two distinct, often concurrent, wave modes are observed, preliminarily identified as electrostatic whistler-mode waves and electron Bernstein waves. Wave intervals range in duration from a few seconds to hours. Both the amplitudes and number of detections of these near-fce waves increase significantly with decreasing distance to the Sun, suggesting that they play an important role in the evolution of electron populations in the near-Sun solar wind. Correlations are found between the detection of these waves and properties of solar wind electron populations, including electron core drift, implying that these waves play a role in regulating the heat flux carried by solar wind electrons. Observation of these near-fce waves is found to be strongly correlated with near-radial solar wind magnetic field configurations with low levels of magnetic turbulence. A scenario for the growth of these waves is presented, which implies that regions of low-turbulence near-radial magnetic field are a prominent feature of the solar wind structure near the Sun.
DOI：
10.1002/2016ja023656
发表时间：
2017-04
期刊：
Journal of Geophysical Research: Space Physics
影响因子：
--
作者：
G. Graham;I. J. Rae;Christopher J. Owen;Andrew P. Walsh;C. Arridge;L. Gilbert;G. Lewis;G. H. Jones;Colin Forsyth;A. J. Coates;J. H. Waite
通讯作者：
G. Graham;I. J. Rae;Christopher J. Owen;Andrew P. Walsh;C. Arridge;L. Gilbert;G. Lewis;G. H. Jones;Colin Forsyth;A. J. Coates;J. H. Waite
影响因子：
7.9
作者：
Narita, Y.;Nakamura, R.;Gary, S. P.
通讯作者：
Gary, S. P.